That's why I asked earlier in this thread, whether the boring out of the block, to fit the liners, ever broke through into the water jacket, in the area you are mentioning.  I once read, that modified engines for 1/4 mile dashes, just fill up the water jackets with "Araldite", or something similar, to prevent the cylinder walls flexing, when they are bored to the limit, & become very thin.

Cheers Banjo 

Nah mine has std liners, theres heaps of meat. 

I think for a std 4k liner the bore is extended form 75 mm out to 77mm, no where near a 5k after 4 succesive rebores at 81.5mm. (80.5 std + 0.25, 0.5, 0.75, 1).

So look its not actually the water jackets that concern me, I can't understand how the 5k can be bored out at all and still have enough meat between the cylinders.

Just look at a std 5k headgasket, there is litteraly no rubber between each cylinder.

I recon itd be like a piece of sheetmetal seperating the cylinders haha

Edited June 18, 20188 yr by rebuilder86

A Finnish company sells 83mm Wiseco pistons so I guess a 5K can take it?

I also don't get it how does the 4K head fit on a 5K with this having so much more bore available...

Not only that, but the part number for the 5kj head is the same part number for the 4ku/j head, confirming it is the same size.

The head is just a flat surface where it sits on the gasket, so it doesn't matter how big the bore is.

Wet liners were used too, they had an O-ring or similar seal at the bottom where they sat in the block and water circulated around the liner.

Check out the twin-cam 4K, philfrederick bored a 4K to take 4AGE 1.6L pistons.  A few guys have done that.

1 hour ago, altezzaclub said:

The head is just a flat surface where it sits on the gasket, so it doesn't matter how big the bore is.

But theres only so much distance between the far side of cylinder one and the far side of cylinder 4. Obviously it works, or we wouldnt be having this discussion haha, but my concerns are about the ability to fit 4 x 83 mm bores inside the dimensions of the 4k head and block.

I think its just all incredibly tight on a 5k, based on all the pics on the net.

Perhaps it would be nice to see 4x oversize 5k pistons sitting upside down on an inverted cylinder head in their rough positions, to see just how small the gaps between them are.

Well, the rest of the head gasket has just one steel ring holding in the fire.. maybe you don't need more between cylinders!

Here's Phil's project, a 4K block over-bored by 6mm.

 

 

Jesus.i started reading that with interest

But i got to the oil pump shimming bit and lost interest because all that does is make the startup oil presaure higher and increase wear, which makes the entire post seem sus.

Ive also had a realy fukn bad day with my car, carby rebuild has sent me backwards, now with a stumbling hesitating intermittent idling car which randomly fills up the throats with fuel, plus completely cracked spark plug insulators and just a bad amell everywhere.

I was just reading that post about the 3kr engine. I knew I wasn't dreaming when I remember one came  out of a  shipping container at the import shop I used to work part time at. It was quickly whisked away to the bosses private collection so I barely got a glimpse of it. I asked the old mechanic about it and he just said pretty rare. But he went on to say he had been to a place in Japan where there was a bunch of them brand new in the crates. If I only knew then....

Hi Graeme,

                    If you can bribe your bank manager, they are still available.

http://www.motorsport-sales.com/index.php?main_page=product_info&cPath=320&products_id=3721

You'd be paying for a few fines, if you popped that one in your girls Rolla !

http://youtu.be/rbovoGOWByk

Cheers Banjo

Edited June 21, 20188 yr by Banjo

hmmmmmm. thats for sale here in the philippines. i should just go get it and be done with this POS in my jeep. Would it be rude to get that and put it in a bunky old jeepney?

 

That guy is dodgy.  Stay well away

hahaah. of course he is, hes here in this country, haha

 

On 6/18/2018 at 2:07 PM, Banjo said:

That's why I asked earlier in this thread, whether the boring out of the block, to fit the liners, ever broke through into the water jacket, in the area you are mentioning.  I once read, that modified engines for 1/4 mile dashes, just fill up the water jackets with "Araldite", or something similar, to prevent the cylinder walls flexing, when they are bored to the limit, & become very thin.

Cheers Banjo 

Sorry mate I thought I'd replied.  

General consensus here, is if they broke through, you have 2 choices. First is send it to the srap metal guy and second is bore out until there is no bore and use "wet sleeves", same as what Keith was saying. A company like darton would be who you'd speak to, I've made a set at work years ago and I'd never, never do it again(the exorbitant price is well worth it). "Grout" or "Hard Block" is what you are thinking of, I wouldn't like to trust it not to move once operating. But it may work, I haven't been game enough to try.haha My problem is that I have 2 std bore 5k blocks to choose from so ill be fine for at least another 15 years or so.